Submission #452489

# Submission time Handle Problem Language Result Execution time Memory
452489 2021-08-04T04:53:12 Z dxz05 Bomb (IZhO17_bomb) C++14
26 / 100
1000 ms 62148 KB
#pragma GCC optimize("Ofast,O2,O3")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

void debug_out() { cerr << endl; }

template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << "[" << H << "]";
    debug_out(T...);
}

#ifdef dddxxz
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define SZ(s) ((int)s.size())
#define all(x) (x).begin(), (x).end()
#define revall(x) (x).rbegin(), (x).rend()

clock_t startTime;

double getCurrentTime() {
    return (double) (clock() - startTime) / CLOCKS_PER_SEC;
}

#define MP make_pair

typedef long long ll;
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const double eps = 0.00001;
const int MOD = 1e9;
const int INF = 1000000101;
const long long LLINF = 1223372000000000555;
const int N = 2e6 + 3e2;
const int M = 2522;

int n, m;
int a[M][M];
bool bomb[M][M];
int dp[M][M];

int sum(int x1, int y1, int x2, int y2){
    if (x1 < 1 || x1 > n || y1 < 1 || y1 > m || x2 < 1 || x2 > n || y2 < 1 || y2 > m) return -1;
    int res = dp[x2][y2];
    res -= dp[x1 - 1][y2];
    res -= dp[x2][y1 - 1];
    res += dp[x1 - 1][y1 - 1];
    return res;
}

int ans = 0;

void fill(int x1, int y1, int x2, int y2){
    if (sum(x1, y1, x2, y2) != (x2 - x1 + 1) * (y2 - y1 + 1)) return;
    for (int i = x1; i <= x2; i++){
        for (int j = y1; j <= y2; j++){
            bomb[i][j] = true;
        }
    }
}

bool check(int A, int B){
    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++) bomb[i][j] = false;
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (bomb[i][j] || !a[i][j]) continue;
            fill(i, j, i + A - 1, j + B - 1);
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (bomb[i][j] || !a[i][j]) continue;
            fill(i - A + 1, j, i, j + B - 1);
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (bomb[i][j] || !a[i][j]) continue;
            fill(i, j + B - 1, i + A - 1, j);
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (bomb[i][j] || !a[i][j]) continue;
            fill(i - A + 1, j - B + 1, i, j);
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (!bomb[i][j] && a[i][j]) return false;
        }
    }

    ans = max(ans, A * B);

    return true;
}

void solve(int TC) {
    cin >> n >> m;

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            char ch;
            cin >> ch;
            a[i][j] = ch - '0';
            dp[i][j] = dp[i][j - 1] + a[i][j];
        }
    }

    for (int j = 1; j <= m; j++){
        for (int i = 1; i <= n; i++){
            dp[i][j] += dp[i - 1][j];
        }
    }

    int A = n, B = m;
    for (int j = 1; j <= m; j++){
        for (int i = 1; i <= n; i++){
            if (a[i][j] == 0) continue;
            int k = i;
            while (k <= n && a[k][j] == 1) k++;
            A = min(A, k - i);
            i = k - 1;
        }
    }

    for (int i = 1; i <= n; i++){
        for (int j = 1; j <= m; j++){
            if (a[i][j] == 0) continue;
            int k = j;
            while (k <= m && a[i][k] == 1) k++;
            B = min(B, k - j);
            j = k - 1;
        }
    }

    if (check(A, B)){
        cout << ans;
        return;
    }

    if (n < m){
        for (int i = 1; i <= n; i++){
            int l = 1, r = m;
            while (l <= r){
                int mid = (l + r) >> 1;
                if (check(i, mid)){
                    l = mid + 1;
                } else r = mid - 1;
            }
        }
    } else {
        for (int i = 1; i <= m; i++){
            int l = 1, r = n;
            while (l <= r){
                int mid = (l + r) >> 1;
                if (check(mid, i)){
                    l = mid + 1;
                } else r = mid - 1;
            }
        }
    }

    cout << ans;

}

int main() {
    startTime = clock();
    cin.tie(nullptr);
    cout.tie(nullptr);
    ios_base::sync_with_stdio(false);

    bool llololcal = false;
#ifdef dddxxz
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    llololcal = true;
#endif

    int TC = 1;
    //cin >> TC;

    for (int test = 1; test <= TC; test++) {
        debug(test);
        //cout << "Case #" << test << ": ";
        solve(test);
    }

    if (llololcal) cerr << endl << "Time: " << int(getCurrentTime() * 1000) << " ms" << endl;

    return 0;
}

Compilation message

bomb.cpp: In function 'int main()':
bomb.cpp:19:20: warning: statement has no effect [-Wunused-value]
   19 | #define debug(...) 42
      |                    ^~
bomb.cpp:199:9: note: in expansion of macro 'debug'
  199 |         debug(test);
      |         ^~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 17 ms 26568 KB Output is correct
4 Correct 18 ms 26572 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Incorrect 1 ms 460 KB Output isn't correct
9 Incorrect 1 ms 460 KB Output isn't correct
10 Correct 1 ms 460 KB Output is correct
11 Correct 1 ms 460 KB Output is correct
12 Correct 1 ms 460 KB Output is correct
13 Correct 1 ms 460 KB Output is correct
14 Correct 1 ms 460 KB Output is correct
15 Incorrect 1 ms 460 KB Output isn't correct
16 Incorrect 1 ms 460 KB Output isn't correct
17 Incorrect 30 ms 1064 KB Output isn't correct
18 Incorrect 14 ms 1116 KB Output isn't correct
19 Incorrect 32 ms 1352 KB Output isn't correct
20 Incorrect 34 ms 1356 KB Output isn't correct
21 Incorrect 12 ms 844 KB Output isn't correct
22 Incorrect 25 ms 1192 KB Output isn't correct
23 Incorrect 56 ms 1360 KB Output isn't correct
24 Incorrect 25 ms 1228 KB Output isn't correct
25 Incorrect 68 ms 1356 KB Output isn't correct
26 Correct 1 ms 1356 KB Output is correct
27 Correct 5 ms 4044 KB Output is correct
28 Execution timed out 1083 ms 4300 KB Time limit exceeded
29 Execution timed out 1091 ms 5452 KB Time limit exceeded
30 Execution timed out 1088 ms 6476 KB Time limit exceeded
31 Execution timed out 1045 ms 5068 KB Time limit exceeded
32 Execution timed out 1056 ms 5964 KB Time limit exceeded
33 Execution timed out 1090 ms 6732 KB Time limit exceeded
34 Execution timed out 1080 ms 4684 KB Time limit exceeded
35 Execution timed out 1088 ms 6732 KB Time limit exceeded
36 Correct 12 ms 6844 KB Output is correct
37 Correct 2 ms 460 KB Output is correct
38 Correct 281 ms 61928 KB Output is correct
39 Correct 2 ms 460 KB Output is correct
40 Execution timed out 1075 ms 16188 KB Time limit exceeded
41 Correct 1 ms 460 KB Output is correct
42 Incorrect 95 ms 1456 KB Output isn't correct
43 Execution timed out 1081 ms 61924 KB Time limit exceeded
44 Execution timed out 1093 ms 6732 KB Time limit exceeded
45 Execution timed out 1084 ms 61948 KB Time limit exceeded
46 Correct 267 ms 61888 KB Output is correct
47 Execution timed out 1098 ms 61832 KB Time limit exceeded
48 Execution timed out 1088 ms 61932 KB Time limit exceeded
49 Correct 268 ms 61952 KB Output is correct
50 Execution timed out 1090 ms 61836 KB Time limit exceeded
51 Execution timed out 1091 ms 61928 KB Time limit exceeded
52 Execution timed out 1087 ms 61824 KB Time limit exceeded
53 Execution timed out 1085 ms 62036 KB Time limit exceeded
54 Execution timed out 1097 ms 61892 KB Time limit exceeded
55 Execution timed out 1092 ms 61924 KB Time limit exceeded
56 Correct 264 ms 62148 KB Output is correct
57 Execution timed out 1086 ms 61844 KB Time limit exceeded
58 Execution timed out 1085 ms 61924 KB Time limit exceeded
59 Execution timed out 1094 ms 61844 KB Time limit exceeded
60 Correct 268 ms 62008 KB Output is correct
61 Correct 265 ms 61992 KB Output is correct
62 Execution timed out 1086 ms 61892 KB Time limit exceeded
63 Correct 367 ms 61952 KB Output is correct
64 Correct 270 ms 61912 KB Output is correct
65 Execution timed out 1091 ms 61892 KB Time limit exceeded
66 Execution timed out 1093 ms 61868 KB Time limit exceeded
67 Execution timed out 1085 ms 61932 KB Time limit exceeded
68 Execution timed out 1093 ms 61892 KB Time limit exceeded
69 Execution timed out 1090 ms 61936 KB Time limit exceeded
70 Execution timed out 1081 ms 48572 KB Time limit exceeded
71 Execution timed out 1092 ms 61920 KB Time limit exceeded
72 Execution timed out 1088 ms 61892 KB Time limit exceeded
73 Execution timed out 1089 ms 61844 KB Time limit exceeded
74 Execution timed out 1103 ms 61876 KB Time limit exceeded
75 Execution timed out 1090 ms 61912 KB Time limit exceeded
76 Execution timed out 1089 ms 61892 KB Time limit exceeded
77 Execution timed out 1083 ms 61920 KB Time limit exceeded
78 Execution timed out 1044 ms 61928 KB Time limit exceeded
79 Execution timed out 1087 ms 61924 KB Time limit exceeded
80 Execution timed out 1083 ms 61928 KB Time limit exceeded
81 Execution timed out 1074 ms 61924 KB Time limit exceeded
82 Execution timed out 1103 ms 61940 KB Time limit exceeded
83 Execution timed out 1085 ms 61888 KB Time limit exceeded
84 Execution timed out 1083 ms 62076 KB Time limit exceeded
85 Execution timed out 1093 ms 61940 KB Time limit exceeded
86 Execution timed out 1094 ms 61892 KB Time limit exceeded
87 Execution timed out 1095 ms 62092 KB Time limit exceeded
88 Execution timed out 1095 ms 61920 KB Time limit exceeded
89 Execution timed out 1101 ms 61892 KB Time limit exceeded
90 Execution timed out 1100 ms 48580 KB Time limit exceeded
91 Execution timed out 1098 ms 61892 KB Time limit exceeded
92 Execution timed out 1093 ms 61924 KB Time limit exceeded
93 Execution timed out 1093 ms 61924 KB Time limit exceeded
94 Execution timed out 1095 ms 61920 KB Time limit exceeded
95 Execution timed out 1093 ms 61936 KB Time limit exceeded
96 Execution timed out 1097 ms 61920 KB Time limit exceeded
97 Execution timed out 1095 ms 62020 KB Time limit exceeded
98 Execution timed out 1100 ms 61892 KB Time limit exceeded
99 Execution timed out 1099 ms 61892 KB Time limit exceeded
100 Execution timed out 1050 ms 61892 KB Time limit exceeded